Improved variable cut-off



attai- Qtib'lwv JOSEPH RANDLES, OF lJERSEY CITY, NEW JERSEY.

` Letters Patent No. 101,162, dated darch 22,

IMPROVED VARIABLE CUT-OFF.

The Schedule referred to in these Letters Patent and making part of the same.

vention.

Figure 2 is a longitudinal vertical section of the same.

Figure 3 is a side elevation of the same, showing the motion of the cut-ofi' valve.

Figure 4 is a similar view, showing the motion of .the main valve.

Similar letters indicate corresponding parts.

This invention relates to a cut-ott' valve, which works on the same seinicireular seat with the main valve, and which is so constructed that its ends will overlap the main valve, motion being imparted toit by means of alink, one end of which connects to a concentric disk, and the other to an eccentric mounted on the crank-shaft ofthe engine, in such a manner that by adjusting the link up or down, the cut-ott` valve can be made to move quicker than the main valve, or slower, or it can beniade to remain stationary during the whole stroke ofthe piston, and by these means the 'steam can be cut ottn at any part of the stroke, and the cnt-ott' can be adjusted while the engine is in motion.

In the drawing, the letter A designates the valvecliest, the bot-toni of which is seinieircular, and forms the seat for the main valve B.

This valve is mounted on a spindle, a., which has its bearings in the sides of the valve-chest, and connccts by a lever, b, and rod c, with an eccentric, (I, mounted on the crank-shaft C of the engine.

The spindle a of the main valve passes through the hollow spindle e of the cut-ofIn valve D, which works on the same seat with the main valve, and is provided withtwo lips f, (see iig. 2,) which overlap the main valve, and serve to cnt off the steam, as will be presently explained.

0n the end of the hollow spindle cis mounted a lever, g, to the end. of which is secured a head, 7i., that forms the guide for the slotted link E, (best seen in iig'. 3.) This link connects at one end by means of a rod, c', with a strap, 7, embracing a concentric disk, 7:,

which is mounted on the crank-shaft C, while the opposite end of said link connects by a rod, l, with a strap, in, which embraces an' eccentric, n, mounted on the crank-shaft. By this arrangement the link is rendered steady, and at the same time left free to he raised or lowered.- This purpose of raising and lowering the link is effectedlby means of a slide, o, which moves in a slotted standard, p, rising from the bed of the engine, and which connects with the link by a rod, q.

On the standard p is marked a scale, yr, divided oil" into eigliths or tenths, or any desirable fractions, and an index, s, secured in the slide o, points to the marks ofthe scale fr.

In practice, the slide o willr be operated by a handlever, and it is held in the requiredposition by a clamping-nut, or by any other suitable locking mechanisin.

If the index s is set to one quarter, the cut-off valve moves quicker than the main valve, andv one ofthe lips, f, begins to overlap the edge of the main valve when the piston has completed one4 quarter of its stroke, (see tig. 2.)

lt' the index is set to one halt' on the scale r, st-caln cut ott at halt' stroke, and so on, the cutoff valve moving slower and slower, until, when the index is set to the naught on the scale, ithe cut-off valve remains stationary, and steam is admitted to the eyliiider throughout the whole stroke of the piston.

By this arrangement a cut-off is obtained which is simple in its construction, and which can be readily adjusted while the engine is in motion.

The valves being seated o n semi-circular seats, and suspended from a spindle, can be readily so 4adj usted that theyde not create any undue friction on their seats, and that they can be moved with coinpaztively little power.

What I claim as new, and desire to secure by Letters Patent, is-

The cut-oli valve l), provided with lips f, and attached to a link, E, which is connected at one end toa concentric disk, la, and at its opposite end to an eccentric, n, and suspended from a slide, o, in combination with the main valve B, constructed and operating substantially in` the manner heiein shown and described.

JOSEPH RANDLES.

Witnesses:

W. HAUFF, (l. WAHLEns. 

